Heating element



y 8, 1956 v. s. CLARK 2,744,996

HEATING ELEMENT Filed Jan. 22, 1953 IN! 'ENTOR.

1 6533271022 (Yup/Z;

United States Patent Ofiice HEATING ELEMENT Vernon S. Clark, Durham Center, Conn., assignor to Safeway Heat Elements, Inc., Middletown, Conn., a corporation of Delaware Application January 22, 1953, Serial No. 332,609

2 Claims. (Cl. 219-46) This invention relates to heating elements and more particularly to flexible woven electrical resistance elements which are adaptable to varied uses such as electrical heating devices and implements, etc.

An object of the invention is to provide a structure having an outer braid or wrap of wire which will act not only as an electrical shielding but will physically help position and protect the insulating wraps over the resistance wire and together with the warp wire to increase the heat dissipating surface area of the element.

A further object is to provide a structure which will permit a higher wattage per element by eliminating low temperature limitations which are present in existing elements due to the nature of the insulating varnishes and plastics used.

A still further object is to provide a structure which will permit a lower resistance wire temperature due to the increased heat dissipating surface of the element.

In addition my invention provides a product which is relatively strong and dimensionally stable while still having sufiicient flexibility to withstand vibration in use as well as distortion during installation.

Further objects and advantages of the invention will be apparent from the following specification and the accompanying drawings, in which Fig. 1 is a plan view of a portion of the heating element embodying my invention.

Fig. 2 is a cross-sectional view taken on the line 2-2 of Fig. 1.

Fig. 3 is a cross-sectional view taken on the line 3-3 of Fig. 1.

2,744,996 Patented May 8, 1956 Fig. 4 is an enlarged detailed view showing my improved structure.

Referring more particularly to the drawings, the heating element 10 is provided with warp wires 11 and a resistance wire 12 acting as a woof. The warp wires may be made of any suitable material but preferably of a metal strand which will tend to dissipate heat transmitted by the resistance element. As shown in Fig. 4 the resistance wire 12 is covered with a wire braid 15 which surrounds and protects the insulating material 16 which may be of spun glass or other insulating material. This makes a much stronger structure since the insulating material is protectedand effectively increases the heat dissipating surface area of the entire element since the heat is transmitted from the braid or wrapping 15 to the strands 11. It also permits higher wattage per element while eleminating low temperature limitations which exist in present day structures.

I claim:

1. A flexible woven electrical heating unit comprising a warp of wire strand and a woof consisting of a resistance wire covered with an insulating material and a braided wire wrap outside of said insulating material to protect it physically and to aid in heat dissipation.

2. A flexible woven electrical heating unit comprising a warp of wire strand and a weft consisting of a resistance wire covered with an insulating material and heat dispersing means, said heat dispersing means consisting of a braided wire wrap outside of said insulating material to protect it physically and to aid in heat dispersion.

References Cited in the file of this patent UNITED STATES PATENTS 1,401,303 Baldwin Dec. 27, 1921 1,799,060 Patermann Mar. 31, 1931 1,944,390 Aceves Jan. 23, 1934 1,963,554 McDill June 19, 1934 1,970,295 Fitzpatrick Aug. 14, 1934 1,989,582 Becker Jan. 29, 1935 2,529,914 Challener Nov. 14, 1950 FOREIGN PATENTS 8,398 Great Britain Apr. 17, 1897 488,826 Great Britain July 14, 1938 

1. A FLEXIBLE WOVEN ELECTRICAL HEATING UNIT COMPRISING A WRAP OF WIRE STRAND AND A WOOF CONSISTING OF A RESISTANCE WIRE COVERED WITH AN INSULATING MATERIAL AND A BRAIDED WIRE WRAP OUTSIDE OF SAID INSULATING MATERIAL TO PROTECT IT PHYSICALLY AND TO AID IN HEAT DISSIPATION. 